Worlds Colliding
by FudgitiveDrake11
Summary: When 4 demigods looking for more demigods get sucked into the world of wizards, Harry Potter is very confused by their strangeness. Note: set in OOTP and after BoO
1. Chapter 1

**Disclaimer: I do not own PJO or HP. I also do not own any of the characters in the story other than my OC's. All credit goes to J.K. Rowling and Rick Riordan.**

 **A/N: Any sort of helpful criticism would be very much appreciated.**

Chapter 1

The air was quiet as the 4 teens walked down the street. Suddenly, a fat male and a skinny man went pelting off through the gloom. The air became noticeably colder, and a sense of despair swept across the street. The teens shivered, but they continued to walk. Suddenly, they saw the two males again. The fat one was one the ground, trying to evade a hooded figure, but his attempts were futile. The skinny one was on his feet, his expression grim. He looked like he had been through this kind of thing before, and pulled out was seemed to be a stick. "Clarisse, Grover, take left!" one of the teens shouted. "Annabeth and I got the right." The teens sprinted off into their places. Clarisse took out her electric spear, while the teens on the right got out a sword and a dagger. All the teens jabbed and slashed at the hooded figures, but it was all in vain. Their weapons seemed to pass right through them like they weren't even there. "My spear does nothing against these!" Clarisse shouted, evidently frustrated. As they watched, the skinny boy yelled something like "Expecto Patronum!" and pointed his wand at the hooded figures. The teens watched in awe as a bright light, that took form as a stag, began to run at the hooded figures. The light seemed to be too much for the hooded figures, and they fled. The 4 teens went over to the skinny kid and bombarded him with questions, and the teen tried to answer them. "Okay, my name is Harry Potter" There was no response from the teenagers. Harry cursed himself. Not only did he do magic outside of school, he did it in the presence of 5 muggles. "What were those hooded figures" asked Annabeth. Harry looked and felt confused. They didn't know who he was, and he was the most famous wizard of all time, so they must be muggles, yet they could still see the figures. "Those were dementors. They are very evil, sucking happiness and warmth wherever they go. I'm surprised you guys could stand it for so long without a Patronus to help ward the effects away. Also, why are you carrying bronze weapons? Aren't they dangerous?" Harry asked. The 4 teens looked at each other, then at the girl with blond hair and gray eyes. She reminded Harry of Malfoy, always plotting. But those gray eyes were gentler, more conceiving, as if she had a lot of knowledge to share. "We'll meet you in the park tomorrow. Hopefully we can explain some of the stuff that you saw today." The 4 teens walked away, muttering in a different language all the while.


	2. Chapter 2

**Disclaimer: I do not own PJO or HP. I also do not own any of the characters in the story other than my OC's. All credit goes to J.K. Rowling and Rick Riordan.**

 **A/N: Any sort of helpful criticism would be very much appreciated.**

Chapter 2

Annabeth yelled in Greek at the 3 other teens, " _Guy's! We almost blew our cover doing that. We'll have to IM Chiron and figure out what to do from there._ "

" _Sorry, Annabeth_ ", the other teens chorused in unison. They got back to where they were staying, a dingy hotel. It wasn't the best living quarters, but it would have to do. On the way to their bedrooms, Grover took a spray bottle that was laying on the floor and filled it with water. They all gathered in Annabeth's bedroom, and Grover started pumping. As light streamed through the window, it made a rainbow. Clarisse threw a drachma into the rainbow and said, "O Iris, goddess of the rainbow accept my offering. Show me Chiron at Camp-Half Blood." The rainbow shimmered, and Chiron's face popped into existence, along with the camp. "Annabeth! Thank the gods. Did you find a new demigod?" asked Chiron.

"Unfortunately, no. We did find something though. There was this clear-sighted mortal, he could see our weapons, but he wasn't a demigod" Annabeth said.

"He was really powerful," put in Grover. "His aura was very strong, he was very faithful in the good, although there was some evil in him too, like it was corrupting him."

Chiron's face darkened. "Wizards" he muttered. "You can tell him everything you can, but you have to keep who you are a secret. If he ever finds out about demigods, a war between demigods and wizards could ignite."

"One last thing," said Annabeth. "His name is Harry Potter."

Chiron's face darkened further. "You can't let him know about your identity, but you have to protect him as best you can. If he falls, the wizarding world breaks into turmoil and falls apart, one witch and wizard at a time."


	3. Chapter 3

**Disclaimer: I do not own PJO or HP. All credit for their characters and such go to Rick Riordan and J.K. Rowling.**

 **A/N: Any sort of helpful criticism would be much appreciated** J

Chapter 3

Annabeth and the others ran towards the park. Harry was already sitting there. "Okay, what happened and who are you?" asked Harry.

"I am Annabeth Chase," said the one that Harry had described as a kinder, wiser Malfoy. "And these are "Percy Jackson, Clarisse La Rue, and Grover Underwood."

"Hi," said Percy. He had sea green eyes and black windswept hair. They might as well have been cousins. Clarisse was buff, and had stringy brown hair and piggy eyes. Grover wore a Rasta cap over his head and had a scraggly goatee.

"What happened?" asked Harry.

"You ask me" said Percy. "I could ask you the same question."

"What did you see?" asked Harry.

"Well, we saw you trying to fend off the dementors, and you created this stag thing and it got rid of them."

"That's basically what happened" said Harry. "What I have is a wand, holly and phoenix feather."

"That's a really powerful wand" said Annabeth. Everyone looked at her in surprise. "What?" Annabeth protested. "I've done some background reading on wizards since last night."

"So, who are you?" asked Percy. "I mean, we all know that you're Harry Potter, but you seemed very surprised when we didn't respond to your name at all."

"Well," Harry started. "I'm kind of a celebrity n the wizarding world. There was this bad dude, his name was Voldemort, and he came to my house when I was about 1. My father tried to hold him off, but at that time, Voldemort was kind of the most powerful wizard of all time. There was nothing he could do. My mother also tried to protect me. Voldemort gave her 3 chances to step aside and let him kill me. My mother refused, and Voldemort killed her too. Then he stepped up to my crib. Apparently, because of my mother's love, when she died, she put this protective shield over me. The killing curse that he sent at me rebounded off of me and hit him instead. I still have this lightning bolt scar, because if a dark curse touches you, it stays like that. He's always found ways to come back though, and he always tries to kill me. Last year, he got fully reformed, and now we don't know what he's going to do next. Now, why do you have bronze weapons?"

All the teens turned to Annabeth. "We have weapons because, well, a lot of people seem to want to kill us. We carry around weapons for self-defense, and the government lets us, so we're authorized to have weapons."

A bird call sounded in the distance. All 5 teenagers looked up, and 5 owls swooped down upon them and dropped letters into their laps.

 **A/N: Sorry for not updating, I had a really big writers block. Please don't kill me.** J


	4. Chapter 4

**Disclaimer: I do not own PJO or HP. All credit for their characters and such go to Rick Riordan and J.K. Rowling.**

 **A/N: Any sort of helpful criticism would be much appreciated**

Chapter 4

Everyone looked at each other in surprise. On the envelope it was addressed with their names first, and then

 **The Park**

 **Mongolia Road**

 **Little Whinging**

 **Surrey**

Harry already knew what they were, but watched as the 4 strange teenagers opened their letters.

"HOGWARTS SCHOOL

 _of_ WITCHCRAFT _and_ WIZARDRY

Headmaster: Albus Dumbledore

 _(Order of Merlin, First Class, Grand Sorc, Chf. Warlock, Supreme Mugwump, International Confed. of Wizards)_

Dear Mr. Jackson,

We are pleased to inform you that you have been accepted at Hogwarts School of Witchcraft and Wizardry. Please find enclosed a list of all necessary books and equipment. Term begins on September 1. We understand that you are new to the culture of wizards and you have made friends with Harry Potter. You may ask him if you need anything. We should get a reply by the 31st of July.

Yours sincerely,

Minerva McGonagall

 _Deputy Headmistress_ " Percy read aloud. Everyone looked at Annabeth again. Harry wondered why they always looked to Annabeth for guidance.

"Yes, we'll go to school with them." Said Annabeth.

"We have to go to school while traveling?" Percy whined. "I don't want to."

"Too bad," said Annabeth. "We're going, end of story."

"Fine" said Percy. He took out his pen, and put the cap on the back of the pen. "Anyone have some spare paper?"

"Here" said Harry. He dug out a spare bit of parchment and handed it to Percy. _We will go to your wizarding school_. Percy wrote. _Thank you for the invitation. That goes for Annabeth, Grover, and Clarisse._ The pen worked like a regular one, but Harry thought it looked like it was glowing. "Harry, how do we send this?" asked Percy. Harry called down one of the owls, and told it to go to Hogwarts and deliver the letter. The owl flew off with Percy's reply still in it's claw.


	5. Chapter 5

**Disclaimer: I do not own PJO or HP. All credit for their characters and such go to Rick Riordan and J.K. Rowling.**

 **A/N: Any sort of helpful criticism would be much appreciated**

Chapter 5

Annabeth and the rest of the teens ran off to where they stayed. When they got there, they immediately IM'd Chiron. "Chiron," Percy whined. "Annabeth is making us go to school."

"What school?" asked Chiron. "Hogwarts" replied Percy, as the teens collapsed into laughter. Chiron smiled, greatly relieved. "The headmaster will be nice enough. Just don't get into trouble unless you're doing it to defend Harry. Your cover story to the wizards is that you are an American transfer from Chiron's Magic and Self-Defense school."

"Chiron, we always get into trouble." replied Percy. "We can't help it. Hopefully Hogwarts will have some magic barriers to protect us and the wizards."

(I'm a linebreak. Don't mind me)

The day of the train, Harry told them, just go to Kings Cross by 11:00. When they got there, Harry was already standing there, with 2 different people, a boy and a girl, the boy with flaming red hair and lots of freckles. The girl had bushy brown hair. "I'm Hermione," said the girl. "And who are you?"

"Well, I'm Percy Jackson, this is Annabeth Chase, this is Grover Underwood, and this is Clarisse La-Rue. We're American transfers from Chiron's Magic and Self-Defense school."

"Never heard of it." replied Hermione.

"I'm Ron Weasley" said the boy with all the freckles.

"Okay, I've never done this before. How do we get on the train?" asked Grover.

"It's simple really. All you have to do is to run straight at the wall between platforms 9 and 10 there was this doorway and it would take you to platform 9 ¾. The teens shrugged at each other and said "Here goes nothing." Then they took a deep breath and sprinted through the barrier.

"Percy?" exclaimed a round-faced kid with a toad n his hands. "What are you doing here?"

"Neville!" exclaimed the 4 teens. "Tell you later. I didn't know you came here after camp was over."

"Yeah, well Chiron wanted me to keep an eye on those guys."

"Who else is here?" asked Percy.

"Fred and George Weasley, Hermione was blessed by Athena, I think Draco is a demigod, but I'm not sure. He wasn't in camp and he hasn't been claimed yet" replied Neville.

"Cool" said Percy. "So, how long is this train ride exactly?"

"7 or 8 hours" replied Neville, and Percy groaned.


	6. Chapter 6

**Disclaimer: I do not own PJO or HP. All credit for their characters and such go to Rick Riordan and J.K. Rowling.**

 **A/N: Any sort of helpful criticism would be much appreciated**

Chapter 6

"So, is there anything to do for 7 to 8 hours as the train goes on?" Percy asked.

"Oh yeah," said Neville. "There's wizards chess, Exploding Snap, and a food trolley that serves candy."

"Oh good," said Percy. "You know how lucky you are right, with absolutely no symptoms from being one, you lucky son of Demeter." When the train left the station and Ron and Hermione were done with prefect duties, Percy was already tapping his fingers on his legs, and Annabeth was in deep conversation with Hermione about school. The boy, Ron, whispered to Percy "Hey, the blond one, Annabeth, if she's talking with Hermione, she's really smart. I want her to play me in chess, see if she's better than me."

"Oh, you're so going down" said Percy. "Annabeth, Ron here wants to see if you can beat him in chess."

"Challenge accepted," said Annabeth, and Ron set up the board. Annabeth beat him easily, and Harry handed Percy a Galleon. After that, they played Exploding Snap, and Gobstones. At one point, Neville showed them all him **_Mimbulus_** _Mimbletonia_.

"Oh, forgot," said Ron. "Guess who the new prefects are for Slytherin."

"Malfoy," said Harry.

"Right in one" said Ron

"Who's Malfoy?" asked Grover.

"A very annoying kid," said Harry. "He's always bragging about how high up his father is in the Ministry, and how he gets certain privileges."

"Let's teach him a lesson" said Clarisse, cracking her knuckles.

When they arrived at the station, a voice called out "First years, over here."

"That's Hagrid" said Harry.

Percy went over to Hagrid and asked him, "We're the exchange students from America. Do we go with you or do we go with the 5th years in the carriage?"

"You go with the carriages," said Hagrid.

From the looks of it, Percy was conversing with the horses

 _Lord, we're honored to have you here_

 _Please don't call me Lord_

 _Very well, Lord_

 _What are you?_

 _Thestrals. Only people who have seen death can see us._

"The horses are called thestrals. Only people who have seen death can see them."

 **A/N: I left out where they go to Diagon Alley because I couldn't think of Ideas. If you want me to put it in there, review and tell me.**


	7. Chapter 7

**Disclaimer: I do not own PJO or HP. All credit for their characters and such go to Rick Riordan and J.K. Rowling.**

 **A/N: Any sort of helpful criticism would be much appreciated**

Chapter 7

Percy POV

Everyone who had died in my demigod life suddenly flashed in front of my eyes. Bianca, Luke, Zoe Nightshade, Ethan Nakamura, Michael Yew, Leo, all of those faces flashed in my mind, and I looked around at the other demigods. Ron abruptly ended it with a rude "So who did you see die?"

"Do you really want to know?" asked Annabeth, sadly.

"Ronald!" exclaimed Hermione. "They have seen deaths, obviously they don't like talking about it. How would you feel if you had been asked a question like 'who did you see die' when you've seen someone die?"

"Sorry," said Ron, although not all that remorseful. They got onto the carriages and they rode off to the castle.

When we arrived at the castle, with Annabeth talking about its amazing architecture all the way, we got off the carriages. When we entered the castle, a woman with a large scroll was tucked under her arm was waiting for us. "My name is Professor McGonagall," she said. "The American's will come with me." "Bye Neville," we called. McGonagall led us down a hall into a large, open, hall. There were a lot of plates. And I was amazed how many kids were in the school.

"Chase, Annabeth" called Professor McGonagall, and Annabeth walked to the seat and put on then hat.


End file.
